1. Field of the Invention
The present invention relates to a clamping device for clamping copied sheets stacked on a bin of a sorter attached to an image forming apparatus such as, for example, a copier, a printer and so on.
2. Description of the Related Prior Art
In the stapling step, the copied sheets ejected on the bin of the sorter must be carried to the stapling position which is disposed beside the bin and where the stapler is disposed, so that the sheet stack is stapled by the stapler. Therefore, the clamping device for the stapler must be composed with a moving unit having clamp levers for clamping the sheets and an unshakable unit, along with which the moving unit is moved toward the clamping position and the stapling position.
In conventional clamping devices, two types were employed. One is that the motor for driving both the cam, which is connected with the clamp levers and the moving unit is mounted on the moving unit of the clamping device. Another is that the solenoid for driving the clamp levers is mounted in the moving unit, where as the motor for driving the moving unit is mounted on the unshakable unit.
However, in these conventional devices, there exist the following drawbacks.
a) The clamping device becomes bulky and complex. b) The moving device becomes heavy, so that a powerful motor is needed for moving the moving unit. c) A flexible electric wire-harness is needed because of the mounting of the solenoid on the moving unit. In addition, the wire harness tends to be break easily. d) The cost becomes higher due to employing the powerful solenoid or highly flexible electrical wire harness.